Titan, an independent republic, was originally colonized from Earth three generations earlier. Duncan's initial challenge is to prepare, physically and intellectually, for the 500-million-mile trip to Earth. Once there, he is caught up in a sweep of new experiences, including the social and political whirl in Washington, a strange visit to a carefully preserved ancient city once prominent in the 20th century, and a search for and meeting with a woman he loved since she visited Titan years before.